Cross Reference to Related Application
None.
Field of the Invention
The present invention relates to compaction apparatus, particularly waste paper balers and to control apparatus therefor responsive to timers and to chamber door, loading door, and/or platen position sensors for detecting possible unsafe operation of the baler and for disabling or otherwise preventing hazardous operation modes.
The present invention relates to compaction equipment for commercial and industrial trash compaction and waste paper baler equipment utilized in paper recycling, which are important and widely used tools in the field of waste management. It is very desirable that this equipment be both efficient and reliable. As with all powerful mechanical equipment, safety hazards should be eliminated to the maximum extent possible, recognizing that there is a tendency for human operators to be less careful than they should be.
Although the invention with which this application is concerned is particularly useful in waste paper balers, this background discussion also concerns itself with trash compactors, since they are both widely used and common forms of equipment. The detailed description below will fully describe balers incorporating the invention. The commercial or industrial waste compactor or baler which will be referred to herein as a xe2x80x9ccompactorxe2x80x9d is found in many situations where there are large volumes of waste to be disposed of in landfills or baled for recycling. Thus, compactors including waste compactors and balers are found in shopping centers, industrial complexes, associated with large discount stores or department stores, and in some residential complexes.
The operation and control of balers according to the invention includes features for controlling the starting, stopping, and reversing of the ram used for driving the platen and compressing the waste paper (usually corrugated paper board from packages and cartons). Features such as interlocks and fault detection functions are included which are important to promote and ensure safety at the point of operation of such powerful mechanical equipment.
Although operational control of compaction apparatus in years past was usually implemented by simple switches and relays, there has been a tendency in recent years to employ computer microprocessors and somewhat sophisticated computer programs and algorithms stored in computer memory in, or associated with, the microprocessor.
U.S. Pat. No. 4,953,109 to Burgis, Pat. No. 5,016,197 to Neumann, et al., and U.S. Pat. No. 5,558,013 to Blackstone, Jr. are examples of trash compaction systems utilizing rather complex computer programs to implement the desired control system (including fullness determination in compaction apparatus). These may be compared with U.S. Pat. No. 3,802,335 to Longo, Pat. No. 4,643,087 to Fenner, et al., and U.S. Pat. No. 6,055,902 to Harrop, et al., which do not employ computer microprocessors but execute simple logic with electrical relays.
Compactors including waste compactors and balers are typically exposed to harsh environments including wide ranges of temperatures and potential exposure to power surges. In addition, it is very important that the compaction equipment operate reliably and operate in a safe manner and not be subject to malfunction because of failure or error conditions in its electrical controls. For that reason, there are many users and others who consider that a relatively simply relay based control system has advantages with regard to reliability, durability, and safety over microprocessor controlled by complex software.
Compactors of the present invention have advantages of simple electro-mechanical related based control systems as shown in U.S. Pat. No. 6,055,902, disclosure of which is incorporated herein by reference, and at the same time provide an advantage of simple maintainability and low component cost that previous electro-mechanical related based control systems do not provide.
Included in the operating and control system are combination magnetic locks and position sensors which operate effectively for locking, releasing, and sensing the position of the loading door and the bale chamber door while reducing the total number of sensors and/or interlocks needed in the system.
The present invention departs from the teaching of prior art waste baler paper systems by providing apparatus which is simple, durable, reliable, and capable of being programmed with special features and which provides safe and uncomplicated operation for operating personnel. An important feature of the present invention is the employment of programmable electronic relay networks in a manner to achieve the simplicity and reliability of electrical relay based control systems while achieving the flexibility, programmability, and reduced component costs associated with electro-mechanical relay or solid state relay control networks.
In addition to providing the features and advantages referred to above, it is an object of the present invention to provide compaction apparatus such as waste paper balers which have the advantages of simple relay-implemented control systems including a safety interlock feature for the bale chamber door, and the loading door while obtaining the advantages of programming flexibility, increased reliability, and reduced component costs.
It is another object of the present invention to utilize combination electromagnetic lock and sensor units for providing control signals to the programmable relay network and receiving control signals from the programmable relay network, thereby reducing the mechanical and electrical elements associated with the control system.
It is yet another object of the present invention to provide waste paper balers with controls utilizing programmable relay networks for timing functions which would otherwise require separate timing elements with less adjustability, greater cost, and greater assembly expense.
It is a further object of the present invention to provide a programmable relay control system for waste paper balers which maximizes simplicity of operation while assuring that electromagnetic interlocks and other safety features prevent improper or unintended operation which could cause property damage or personal injury.